As shown on their web site the opening hours are
Cellar Door Open 7 Days
10.30am—5.00pm (Which includes Tuesdays)
Closed New Years Day, Good Friday and Christmas Day.
Opening times as per other posts. I recommend doing the Taste your birth year experience. Even though I live only 5 minutes from Seppeltsfield, got married there and have lived in the Barossa all my life, there is still things that you don't get to see on the average tour. Cheers
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